contrib/lisp/org-eldoc.el

   1 ;;; org-eldoc.el --- display org header and src block info using eldoc
   2
   3 ;; Copyright (c) 2014 Free Software Foundation, Inc.
   4
   5 ;; Author: Łukasz Gruner <lukasz@gruner.lu>
   6 ;; Maintainer: Łukasz Gruner <lukasz@gruner.lu>
   7 ;; Version: 6
   8 ;; Package-Requires: ((org "8"))
   9 ;; URL: https://bitbucket.org/ukaszg/org-eldoc
  10 ;; Created: 25/05/2014
  11 ;; Keywords: eldoc, outline, breadcrumb, org, babel, minibuffer
  12
  13 ;; This file is not part of Emacs.
  14
  15 ;; GNU Emacs is free software: you can redistribute it and/or modify
  16 ;; it under the terms of the GNU General Public License as published by
  17 ;; the Free Software Foundation, either version 3 of the License, or
  18 ;; (at your option) any later version.
  19
  20 ;; GNU Emacs is distributed in the hope that it will be useful,
  21 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  22 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  23 ;; GNU General Public License for more details.
  24
  25 ;; You should have received a copy of the GNU General Public License
  26 ;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
  27
  28 ;;; Commentary:
  29
  30 ;;; Changelog:
  31
  32 ;; As of 01/11/14 switching license to GPL3 to allow submission to org-mode.
  33 ;; 08/11/14 switch code to automatically define eldoc-documentation-function, but don't autostart eldoc-mode.
  34
  35 ;;; Code:
  36
  37 (require 'org)
  38 (require 'ob-core)
  39 (require 'eldoc)
  40
  41 (defgroup org-eldoc nil "" :group 'org)
  42
  43 (defcustom org-eldoc-breadcrumb-separator "/"
  44   "Breadcrumb separator."
  45   :group 'org-eldoc
  46   :type 'string)
  47
  48 (defcustom org-eldoc-test-buffer-name " *Org-eldoc test buffer*"
  49   "Name of the buffer used while testing for mode-local variable values."
  50   :group 'org-eldoc
  51   :type 'string)
  52
  53 (defun org-eldoc-get-breadcrumb ()
  54   "Return breadcrumb if on a headline or nil."
  55   (let ((case-fold-search t) cur)
  56     (save-excursion
  57       (beginning-of-line)
  58       (save-match-data
  59         (when (looking-at org-complex-heading-regexp)
  60           (setq cur (match-string 4))
  61           (org-format-outline-path
  62            (append (org-get-outline-path) (list cur))
  63            (frame-width) "" org-eldoc-breadcrumb-separator))))))
  64
  65 (defun org-eldoc-get-src-header ()
  66   "Returns lang and list of header properties if on src definition line and nil otherwise."
  67   (let ((case-fold-search t) info lang hdr-args)
  68     (save-excursion
  69       (beginning-of-line)
  70       (save-match-data
  71         (when (looking-at "^[ \t]*#\\+\\(begin\\|end\\)_src")
  72           (setq info (org-babel-get-src-block-info 'light)
  73                 lang (propertize (nth 0 info) 'face 'font-lock-string-face)
  74                 hdr-args (nth 2 info))
  75           (concat
  76            lang
  77            ": "
  78            (mapconcat
  79             (lambda (elem)
  80               (when (and (cdr elem) (not (string= "" (cdr elem))))
  81                 (concat
  82                  (propertize (symbol-name (car elem)) 'face 'org-list-dt)
  83                  " "
  84                  (propertize (cdr elem) 'face 'org-verbatim)
  85                  " ")))
  86             hdr-args " ")))))))
  87
  88 (defun org-eldoc-get-src-lang ()
  89   "Return value of lang for the current block if in block body and nil otherwise."
  90   (let ((case-fold-search t))
  91     (save-match-data
  92       (when (org-between-regexps-p ".*#\\+begin_src"
  93                                    ".*#\\+end_src")
  94         (save-excursion
  95           (goto-char (org-babel-where-is-src-block-head))
  96           (car (org-babel-parse-src-block-match)))))))
  97
  98 (defvar org-eldoc-local-functions-cache (make-hash-table :size 40 :test 'equal)
  99   "Cache of major-mode's eldoc-documentation-functions,
 100  used by \\[org-eldoc-get-mode-local-documentation-function].")
 101
 102 (defun org-eldoc-get-mode-local-documentation-function (lang)
 103   "Check if LANG-mode sets eldoc-documentation-function and return its value."
 104   (let ((cached-func (gethash lang org-eldoc-local-functions-cache 'empty))
 105         (mode-func (intern-soft (format "%s-mode" lang)))
 106         doc-func)
 107     (if (eq 'empty cached-func)
 108         (when (fboundp mode-func)
 109           (with-temp-buffer
 110             (funcall mode-func)
 111             (setq doc-func (and eldoc-documentation-function
 112                                 (symbol-value 'eldoc-documentation-function)))
 113             (puthash lang doc-func org-eldoc-local-functions-cache))
 114           doc-func)
 115       cached-func)))
 116
 117 (declare-function c-eldoc-print-current-symbol-info "c-eldoc" ())
 118 (declare-function css-eldoc-function "css-eldoc" ())
 119 (declare-function php-eldoc-function "php-eldoc" ())
 120 (declare-function go-eldoc--documentation-function "go-eldoc" ())
 121
 122 (defun org-eldoc-documentation-function ()
 123   "Return breadcrumbs when on a headline, args for src block header-line,
 124   calls other documentation functions depending on lang when inside src body."
 125   (or
 126    (org-eldoc-get-breadcrumb)
 127    (org-eldoc-get-src-header)
 128    (let ((lang (org-eldoc-get-src-lang)))
 129      (cond ((or
 130              (string= lang "c") ;; http://github.com/nflath/c-eldoc
 131              (string= lang "C")) (when (require 'c-eldoc nil t)
 132                                    (c-eldoc-print-current-symbol-info)))
 133            ;; https://github.com/zenozeng/css-eldoc
 134            ((string= lang "css") (when (require 'css-eldoc nil t)
 135                                    (css-eldoc-function)))
 136            ;; https://github.com/zenozeng/php-eldoc
 137            ((string= lang "php") (when (require 'php-eldoc nil t)
 138                                    (php-eldoc-function)))
 139            ((or
 140              (string= lang "go")
 141              (string= lang "golang")) (when (require 'go-eldoc nil t)
 142                                         (go-eldoc--documentation-function)))
 143            (t (let ((doc-fun (org-eldoc-get-mode-local-documentation-function lang)))
 144                 (when (fboundp doc-fun) (funcall doc-fun))))))))
 145
 146 ;;;###autoload
 147 (defun org-eldoc-load ()
 148   "Set up org-eldoc documentation function."
 149   (interactive)
 150   (setq-local eldoc-documentation-function #'org-eldoc-documentation-function))
 151
 152 ;;;###autoload
 153 (add-hook 'org-mode-hook #'org-eldoc-load)
 154
 155 (provide 'org-eldoc)
 156
 157 ;; -*- coding: utf-8-emacs; -*-
 158
 159 ;;; org-eldoc.el ends here